Sprue-pin for molding-machines.



Patented Mar. II, 1902.

C. R. DAVlS.

SPRUE PIN FOR MOLDING MACHINES. 7

(Application filed Nov. 28, 1901.)

(No Model.)

NVENTOR 1 NITED STATES price.

Parnwr CALVIN R. DAVIS, OF SOUTH BEND, INDIANA, ASSIGNOR TO OLIVER A OHILLED PLOW WORKS, OF SOUTH BEND, INDIANA.

SPRUE-PIN FOR MOLDING=MACHINES.

SPECIFICATION forming part of Letters Patent No. 695,146, dated March 11, 1902. Application filed November 26, 1901. Serial No. 83,803. (No model.)

To all whom it may concer /t:

Be it known that I, CALVIN R. DAVIS, of South Bend, in the county of St. Joseph and State of Indiana, have invented certain new and useful Improvements in Sprue-Pins for Molding-Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in sprue-patterns for molding-machines, and is designed particularly as an improvement on the construction disclosed in my application, Serial No. 76,395, filed September 24:, 1901.

The main object of this improvement is to provide a device of the character described so constructed that it may be secured to a very thin pattern-plate, thus dispensing with the necessity of the heavy pattern-plate disclosed in theapplication above referred to.

A further object is to so simplify the construction that it can be attached to any pattern-plate at any part of the surface of the latter without any previous preparation of said plate.

With these ends in view my invention consists in the parts and combinations of parts, as will be more fully explained, and pointed out in the claims.

In the accompanying drawings, Figure'l is a view in longitudinal section of my improved device applied to a pattern-plate. Fig. 2 is a View in section of the sprue-pin and head, showing the device employed for removing these parts from the sand. Fig. 3 is a view showing the device in position in the sand before compression. Fig. 4 is a similar view showing the parts after compression, and Fig. 5 is a View of the cap-adjusting key.

1 represents the pattern-plate of a mold, and 2 my improved telescopic sprue-pattern, consisting of a base or sprue-pin stool 3, pin 4, and head 5. The stool 3 comprises a base and a conical body reduced at its upper end to form the shoulder 7. The base is provided with a plurality of screw-holes for its attach-. ment to the pattern-plate 1, and as the base is flat on its bottom it will be seen that it can be secured to a pattern-plate of any thickness. In the device disclosed in my previous application the pattern-plate is recessed for the reception of the spring which yieldingly supports the pin and head, while in the present case the spring is carried within the pin and head. Hence the stool can be screwed to any thickness of pattern-plate and to any portion of the face of the latter without recessing or otherwise preparing the pattern-board therefor.

The pin 4 is cylindrical in shape and is provided at its lower end with an opening to receive the upper reduced end of the stool 3 and is adapted when the parts are assembled to rest on the shoulder 7. This pin is of the same diameter as the shoulder 7, so that when the pin is in place it forms a smooth cylin drical continuation of the stool.

The head 5 is exteriorly in the form of an inverted truncated cone and internally is of two diameters, both of which are cylindrical in shape. The lower or smaller bore 8 is of a size to snugly fit the body of the pin, while the upper and larger bore receives the flanged upper end of the pin, the movement of the latter within the head being limited by the shoulder 9, formed at the juncture of the two bores. This pin fits snugly within the head, so that there is no chance Whatever for lateral play, and it is recessed in its upper end for the reception of the lower end of the spring 10, which latter rests on the felt or other washer 15, located within the recess inthe pin. This spring projects upwardly beyond the flanged end of the pin and rests against the cap 11, screwed into the upper end of the head. As the cap is screwed into the head and forms an abutment for one end of the spring it will be seen that the tension of the spring can be increased or diminished by simply adjusting the cap 11. The cap rests normally below the plane of the upper end of the head, and the portion of the bore immediately above the cap is chambered out or slightly dovetailed to receive the ends of the springbail 12, which latter is employed for removing the head and its attached pin from the sand. The cap is provided on its lower face with a recess designed to receive the end of the spring, and thus hold the latter centrally within the head, and is provided in its upper face with two or more recesses, into which the pins 13 of the key 14 are inserted when it is desired or necessary to remove or adjust the cap.

The operation of my device is as follows: When a mold is to be made, the stool (if not already on) is secured in proper position on the pattern-plate and the pin with the head thereon is placed in position on the stool. A sand-box and flask are then placed over the pattern-plate and filled with sand, the superfluous sand on the top being removed, so as to expose the top of the head. This flask, with sand and pattern-plate, is then moved under the press or molding-machine and the platen or plunger of the latter caused to rise, which compresses or compacts the sand and at the same time telescopes the sprue pin within the head. After the proper degree of compression of the sand has been attained the platen or plunger of the press is caused to descend, and as the latter descends the spring acting on the pin causes the latter to move out of the head and acting on the stool forces the latter and its attached pattern-plate away from the packed sand. The flask and mold are then removed from the press and the pin and head withdrawn from the sand by inserting the spring-bail in the open end of the head, as shown. With this construction the sprue-pin changes its length temporarily to conform to the compression of the moldingmachine, and as the pressure is withdrawn the pin elon gates or assumes its normal length, thus forcing the stool from the sand and leaving the pin proper free to be withdrawn, thus forming a perfectly clean sprue-hole for the introduction of the molten metal.

It is evident that changes in the construction and relative arrangement of the several parts might be made without avoiding my invention, and hence I would have it understood that I do not restrict myself to the particular construction and arrangement of parts shown and described; but,

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. A sprue-pattern consisting of a stool and a pin and a head, the said pin being loosely seated on the stool so as to be removable therefrom by a straight pull, and means interposed between the pin and head whereby the latter is permitted to yield under a longitudinal pressure thereagainst.

2. A sprue-pattern consisting of a connected pin and head, a stool adapted to be secured to the pattern-plate and loosely support the pin and head, whereby the latter may be removed by a straight pull, and a spring interposed between the pin and head for normally holding these parts elongated.

3. A sprue-pattern, consisting of a stool, a hollow conical head, a pin mounted within the head, a spring in the head and bearing against the pin and a screw-cap for regulating the tension of the spring.

4. A sprue-pattern consisting of a conical stool, a hollow inverted conical head, a pin carried by said head and adapted to be loosely seated on the upper end of the conical stool and removable therefrom by a straight pull and a spring within the head and bearing against the pin.

5. A sprue-pattern, consisting of a conical stool, a hollow inverted conical head, a pin carried by said head, a spring located within the head and bearing against the pin and an adjustable cap for regulating the tension of the spring.

6. A sprue-pattern, consisting of a conical stool, a hollow inverted conical head, a pin carried by the head and provided with a recess in its lower end to receive the upper end of the stool and a cap closing the upper end of the head.

7. A sprue-pattern, consisting of a conical stool, a hollow inverted conical head, a pin carried by the head and provided with a recess at one end to receive the smaller end of the stool, and a recess in its other end to receive one end of a spring, a spring seated in said recess in the pin, and a cap secured to said head and forming a seat for the other end of said spring.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

CALVIN R. DAVIS.

Witnesses:

JNo. W. HARBoN, THOS. A. FREEMAN. 

